John 3:4 - Clarke's commentary and critical notes on the Bible

Nicodemus saith unto him, How can a man be born when he is old? can he enter the second time into his mother's womb, and be born? How can a man be born when he is old? - It is probable that Nicodemus was pretty far advanced in age at this time; and from his answer we may plainly perceive that, like the rest of the Jews, and like multitudes of Christians, he rested in the letter, without paying proper attention to the spirit: the shadow, without the thing signified, had hitherto satisfied him. Our Lord knew him to be in this state, and this was the cause of his pointed address to him.